Pneumatic Conveyor Systems

Chemical Engineering 134

Semester 1 AY 2014-2015

Girro Rigor

Pneumatic Conveyor Systems

• Basics

• Equipment Types

• Diagrams

• Parts and Functions

• Pros and Cons

• Applications

Pneumatic Conveyor Systems

Transfer particulate bulk materials through enclosed horizontal or vertical conveying lines

• Motive force:

» Pressure differential

» Air (or other gas) flow

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Pneumatic Conveyor Systems

Classified by operating principle:

I. Dilute Phase Conveyor

A. Dilute Phase Pressure Conveyor

B. Dilute Phase Vacuum Conveyor

II. Dense Phase Conveyor

A. Dense Phase Pressure Conveyor

B. Dense Phase Vacuum Conveyor

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Pneumatic Conveyor Systems

Dilute Phase Conveyor

• Particles: suspended in conveying gas

• Transport: ↓ P and ↑ V

Dense Phase Conveyor

• Particles: not suspended in conveying gas

• Transport: ↑ P and ↓ V

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Pneumatic Conveyor Systems

I.A. Dilute Phase PressureConveyor System

• Most common

• For powders/granules; non-abrasive; non-fragile; ↓ ρB (<62 lb/ft3)

» Ex. Sugar, flour, activated carbon, NaHCO3

• Single source to multiple destinations

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Pneumatic Conveyor Systems

I.B. Dilute Phase VacuumConveyor System

• For compressible; fibrous; toxic

» Ex. Wood shavings, cotton fibers, asbestos

• Multiple sources to a single destination

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Pneumatic Conveyor Systems

II.A. Dense Phase PressureConveyor System

• Gentle (↓ materials degradation, abrasion)

• For abrasive; fragile; intermediate to small particles (<0.75 in)

» Ex. Silica sand, alumina, candies, resins, puffed rice cereal

• For long distances (>250 ft)

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Pneumatic Conveyor Systems

II.B. Dense Phase VacuumConveyor System

• Gentle (↓ materials degradation, abrasion)

• For abrasive; fragile; smallparticles

• For short distances (<200 ft)

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Pneumatic Conveyor Systems

Dilute,Pressure

Dilute,Vacuum

Dense,Vacuum

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Dense,Pressure

Pneumatic Conveyor Systems

Air movers

• PD Blower (Dilute); Compressor, Vacuum Pump (Dense)

Air-material receiver

• Receiving Bin

Storage and collection

• Silo; Hopper, Transporter/Pressure Vessel

Carrier

• Conveying Line

++

• Filters, Valves, Nozzles

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Pneumatic Conveyor Systems

Advantages

• Gives more flexibility than mechanical conveyors

• Occupy less space

• Totally enclosed

• Low maintenance

Disadvantages

• High power requirement

• Large dust collection system

• Cannot be used for:

» Large particles

» High bulk density materials

» Sticky materials

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Bulk Bag and Bag Dump Pneumatic Batching-Blending System

Major ingredients sourced from bulk bags are weighed automatically while minor, pre-weighed ingredients are dumped manually.

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Bulk Bag Filler with Pneumatic Material Feed System

The filter receiver's load cells transmit weight gain information to the system controller that stops the conveyor once a pre-selected batch weight, equivalent to that of one full bulk bag, has been accumulated.

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Pneumatic grain conveying equipment

Vacuum-pressure rail unloadingdilute and dense phase

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Silo blending and in-plant delivery

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications

Carbon black rail car unloading; vacuum and dense phase unloading

Basics Equipment Types Diagrams Parts and Functions Pros and Cons Applications